Abstract | PURPOSE:
DA-125 [(8S,10S)-8-(3-Aminopropanoyloxyacetyl)-10-[(2,6-dideoxy-2-fluoro-alpha-L-talopyranosyl) oxy]-7,8,9,10-tetrahydro-6,8,11-trihydroxy-1-methoxy-5,12- naphthacene-dione hydrochloride] is a novel anthracycline derivative with anticancer activity. In the present study, we compared the cytotoxicity of DA-125 with that of doxorubicin in H4IIE rat hepatoma cells and investigated the mechanistic basis. Because activation of MAP kinases, in particular c-Jun N-terminal kinase (JNK), is implicated in apoptotic cell death, the signaling pathways responsible for DA-125-induced apoptosis were studied. METHODS: Cytotoxicity and apoptosis were measured in H4IIE cells and cells were stably transfected with a dominant-negative mutant of JNK1 (JNK1-) by MTT and TUNEL assays. Inhibition of topoisomerase II activity was determined in vitro. Drug accumulation and DNA binding affinity were determined by fluorescence spectroscopy. RESULTS: The cytotoxicity of DA-125 was greater than that of doxorubicin (IC50 11.5 vs 70 microM). DA-125 induced apoptosis with 30-fold greater potency than doxorubicin. Inhibition of topoisomerase II by DA-125 was fourfold greater. The presence of excess beta-alanine, a DA-125 moiety, failed to alter cytotoxicity and accumulation of DA-125, indicating that the improved cytotoxicity of DA-125 did not result from the beta-alanine moiety. Greater cellular accumulation of DA-125 correlated with its high-affinity DNA binding. Although neither PD98059 nor SB203580 altered the degree of cytotoxicity induced by DA-125, JNK1 cells exhibited about a twofold greater viability than control cells. DA-125-induced apoptosis was also decreased in JNK1- -transfected cells. CONCLUSIONS:
DA-125 potently inhibited topoisomerase II activity and induced apoptosis by a high rate of prooxidant production. DA-125 exhibited high-affinity DNA binding with improved cellular drug accumulation. Apoptosis induced by DA-125 involved the pathway of JNK1, but not ERK1/2 or p38 kinase.
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Authors | S G Kim, M Sung, K W Kang, S H Kim, M H Son, W B Kim |
Journal | Cancer chemotherapy and pharmacology
(Cancer Chemother Pharmacol)
Vol. 47
Issue 6
Pg. 511-8
(Jun 2001)
ISSN: 0344-5704 [Print] Germany |
PMID | 11459204
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Antineoplastic Agents
- DNA, Neoplasm
- Enzyme Inhibitors
- Topoisomerase II Inhibitors
- beta-Alanine
- 7-O-(2,6-Dideoxy-2-fluoro-alpha-talopyranosyl)adriamycinone- 14-beta-alaniate hydrochloride
- Doxorubicin
- Peroxidase
- JNK Mitogen-Activated Protein Kinases
- Mitogen-Activated Protein Kinases
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Topics |
- Animals
- Antineoplastic Agents
(metabolism, pharmacology)
- Carcinoma, Hepatocellular
(drug therapy, metabolism)
- DNA, Neoplasm
(metabolism)
- Doxorubicin
(analogs & derivatives, metabolism, pharmacology)
- Enzyme Inhibitors
(pharmacology)
- JNK Mitogen-Activated Protein Kinases
- Liver Neoplasms
(drug therapy, metabolism)
- Mitogen-Activated Protein Kinases
(metabolism)
- Peroxidase
(metabolism)
- Rats
- Topoisomerase II Inhibitors
- Tumor Cells, Cultured
- beta-Alanine
(metabolism)
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